Wearable, unsupervised transcranial direct current stimulation (tDCS) device for movement disorder or memory therapy

ABSTRACT

The present invention relates to a system and methods for noninvasively providing therapy for movement disorder symptoms. The present invention provides such a therapy system which provides trans-cranial direct current stimulation (tDCS) in order to treat those symptoms and the disorders. The present invention further provides such tDCS therapy while the subject sleeps in order to minimize the time required and impact of the therapy on the subject&#39;s waking life. The system, methods, and devices of the present invention are intended to provide a low-dose electrical current, trans-cranially, to a specific area of the subject&#39;s brain while he or she sleeps in order to decrease the occurrence, severity, and duration of the symptoms of movement disorders. The present invention aims to reduce the amount of medication necessary, counteract the effects of medication wearing off during sleep, and to overall improve the quality of life of subjects suffering from movement disorders.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/953,801 which was filed on Nov. 30, 2015 and which was a continuationof U.S. patent application Ser. No. 14/461,846 which was filed on Aug.18, 2014 and issued as U.S. Pat. No. 9,227,056 on Jan. 5, 2016, andwhich was a continuation of U.S. patent application Ser. No. 14/045,336which was filed on Oct. 3, 2013 and which issued as U.S. Pat. No.8,843,201 on Sep. 23, 2014, and which was a continuation of U.S. patentapplication Ser. No. 13/633,358 filed on Oct. 2, 2012, and which issuedas U.S. Pat. No. 8,583,238 on Nov. 12, 2013.

STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH OR DEVELOPMENT

The U.S. Government has a paid-up license in this invention and theright in limited circumstances to require the patent owner to licenseothers on reasonable terms provided for by the terms of the Phase Igrant number 1R43NS077652-01A1 awarded by the National Institute ofNeurological Disorders and Stroke.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to therapeutic medical apparatus, systems,devices and/or methods, and more particularly, to apparatus and methodsfor using neural stimulation to alleviate the symptoms of movementdisorders, such as those associated with Parkinson's disease, essentialtremor, dystonia, and Tourette's syndrome, including tremor,bradykinesia, rigidity, gait/balance disturbances, and dyskinesia, aswell as sleep disorders such as REM sleep behavior disorder and restlessleg syndrome.

2. Technical Background

There has been tremendous growth and active research into diseasemodifying agents of Parkinson's disease (PD) as well as pharmaceuticaland surgical treatments for associated motor symptoms. PD, aneurodegenerative disorder that affects the motor system, ischaracterized by tremor, slowed movements (bradykinesia), and rigidity.With approximately 1.5 million Americans diagnosed with PD and over50,000 new cases each year, the need for intervention to both treat thesymptoms and alter disease progression cannot be understated. Overnighttranscranial direct current stimulation (tDCS), which provides anoninvasive painless electrical polarization to the cerebral cortex,could provide a non-pharmaceutical and non-surgical therapeutic optionto complement current treatments for PD motor symptoms and related sleepdisturbances.

PD is caused by a loss of dopamine-producing neurons in the substantianigra, but the exact reason for neurodegeneration remains unknown. Acurrent trend in the treatment of diseases identified as beingassociated with the central nervous system is the stimulation of targetareas of the central nervous system to effect therapeutic benefit. Suchstimulation has been accomplished with, for example, implantedelectrodes that deliver electrical stimulation to target brain regions;one class of electrical neural stimulation devices has been categorizedunder the name “deep brain stimulation” (DBS). Although the exactneurological mechanisms by which DBS therapies succeed are complex andare not yet fully understood, such therapies have proven effective intreating Parkinson's disease motor symptoms (such as tremor,bradykinesia, rigidity, and gait disturbances), and investigation intothe use of DBS for the treatment of this and other neurological andmental health disorders, including major depression,obsessive-compulsive disorder, tinnitus, obesity, criminal tendencies,and antisocial disorders, is ongoing.

Typically, medication for Parkinson's disease (PD) consists of Levodopato alleviate symptoms. Over time, however, the medication has reducedefficacy and shows increased occurrence of side effects such asdyskinesias. Once side effects outweigh benefits, subjects consider deepbrain stimulation (DBS). An electrode/wire lead is implanted in aspecific location in the brain which shows hyperactivity in PD subjectsand is sensitive to electrical stimulation. PD target sites are thesubthalamic nucleus (STN) or globus pallidus internus (GPi). Theessential tremor and Parkinson tremor target site is generally theventral intermedius nucleus of the thalamus (VIM). Electrical pulsescharacterized by amplitude (volts), current (amps), frequency (Hz), andpulse width (microseconds) are regulated by an implantable pulsegenerator (IPG) placed beneath the skin on the chest. Stimulationaffects motor symptoms on the contralateral side, i.e., right sidetremor will be treated on the left brain. After a subject has beenimplanted and recovered, programming sessions will fine tune stimulationsettings described above in order to minimize symptom severity, minimizeside effects, and maximize IPG battery life span. Although medication isnot eliminated, it is typically reduced significantly. DBS efficacydecreases over time as the body adjusts to stimulation and proteinbuildup around electrode lead attenuates electrical field. Programmingsessions are required throughout the subject's lifetime, though thefrequency of adjustments are typically greater at first.

A typical implanted DBS stimulation lead consists of a thin insulatedneedle comprising four platinum/iridium electrodes spaced 0.5 or 1.5 mmapart along the length of the lead. One or multiple leads may beimplanted in a target brain region or regions to providesymptom-inhibiting high-frequency stimulation, although some researchsuggests that excellent results can be achieved even when the lead isimplanted distant from a target region. A DBS lead is connected to animplantable pulse generator (IPG), which serves as a controller andpower source, via an extension cable tunneled subcutaneously to asubcutaneous pocket in the chest or abdominal cavity. The IPG typicallyincludes a battery and circuitry for telemetered communication with anexternal programming device used to adjust, or “tune,” DBS leadstimulation parameters, which may include stimulation frequency,amplitude, pulse width (or wavelength), and contact configuration (thatis, the selection of which electrodes are utilized from among the fourelectrodes available on a lead, and, if two or more electrodes areactive, the relative polarity of each). These parameters are initiallyset during implantation surgery and are then further fined-tuned in theoutsubject clinic or in a doctor's office following surgery to maximizetherapeutic benefit and minimize undesirable stimulation-induced sideeffects. The first such tuning session usually takes place several weeksfollowing implantation surgery, after the subject has recovered andinflammation at the lead placement site has subsided.

While existing drug and DBS treatments do alleviate motor symptoms, newdata has documented that tDCS has therapeutic potential in PD bothacutely and chronically. tDCS is a noninvasive brain simulation modalityin which direct current is steadily applied via electrodes on thesurface of the scalp. tDCS polarizes the brain using weak directcurrents that are applied via scalp electrodes. Finite element models(FEM) show that current densities in the cortex resulting from tDCS are2-3 orders of magnitude lower than action potential thresholds, thus,tDCS does not stimulate cortex, but rather modulates corticalexcitability. Fregni et al. found that Unified Parkinson's DiseaseRating Scale (UPDRS) scores improved significantly after anodalstimulation to primary motor cortex (M1) (p<0.001). F. Fregni et al.,Noninvasive cortical stimulation with transcranial direct currentstimulation in Parkinson's disease, Mov. Disord. 2006 October;21(10):1693-1702. The current standard in evaluating the severity ofmovement disorder symptoms in Parkinson's disease is the UnifiedParkinson's Disease Rating Scale (UPDRS) used to score motor tests, manyof which involve repetitive movement tasks such as touching the nose anddrawing the hand away repeatedly, or rapidly tapping the fingerstogether. A battery of exercises, typically a subset of the upperextremity motor section of the UPDRS, is normally completed during DBSlead placement surgery and subsequent programming sessions to evaluateperformance while a clinician qualitatively assesses symptoms. Each testis evaluated by a clinician based solely on visual observation andgraded on a scale that ranges from 0 (normal) to 4 (severe). Morerecently, Benninger et al. found that tDCS did not significantly improveoverall UPDRS scores; however, bradykinesia, the primary complaint inmany PD subjects, did significantly decrease (p<0.0001). D. H. Benningeret al., Transcranial direct current stimulation for the treatment ofParkinson's disease, Journal of Neurology, Neurosurgery & Psychiatry.2010 September; 81(10):1105-1111. The fact that Chen states that tDCS asa treatment for PD is “not ready for prime time,” but does emphasizethat pilot studies are needed and “useful adjunctive treatments areclearly welcome,” serves to point out that tDCS for movement disordertherapy is far from known in the art, but has shown potential forutility in this field. R. Chen, Transcranial direct current stimulationas a treatment for Parkinson's disease—interesting, but not ready forprime time, Journal of Neurology, Neurosurgery & Psychiatry. 2010 June;81(10):1061-1061. In addition to likely improving motor function in PDsubjects, tDCS has been established and shown to have efficacy invarious other fields, such as to aid in rehabilitation after stroke,improve motor learning in healthy adults, improve memory in subjectswith Alzheimer's disease, improve mood in subjects with majordepression, and improve memory during slow-wave sleep. Recent studieshave shown that DBS during sleep either directly or as a function ofincreased mobility improves sleep quality in PD subjects, suggesting thetDCS may too improve sleep quality. A. W. Amara et al., The effects ofdeep brain stimulation on sleep in Parkinson's disease, Ther. AdvNeurol. Disord. 2011 January; 4(1):15-24.

Unlike other noninvasive stimulation modalities such as transcranialelectrical stimulation (TES) and rapid transcranial magnetic stimulation(rTMS) that can be costly, painful, and cause side effects includingseizures and psychotic symptoms, tDCS is painless, poses few sideeffects, and is ideal for home use since it can be provided in aninexpensive and compact package. The only sensation from tDCS istingling during stimulation onset. This is in sharp contrast to rTMS,which induces a strong scalp sensation along with facial and scalpmuscle twitches. Additionally, rTMS systems are extremely bulky, requirea large power supply, cost $20,000-$100,000, and are not suitable forhome use. Conversely, the disclosed tDCS system will be specificallydesigned for home use and be much more cost effective.

In light of the above, it is therefore an object of the presentinvention to provide a noninvasive movement disorder therapy system, andmethods of using the same, which can reduce the severity and frequencyof a subject's symptom occurrence, improve the subject's sleep quality,and improve the subject's overall quality of life while reducing theamount of the subject's waking life required to receive such therapy.

SUMMARY OF THE INVENTION

The present invention relates to a system and methods for noninvasivelyproviding therapy for movement disorder symptoms. The present inventionprovides such a therapy system which provides transcranial directcurrent stimulation (tDCS) in order to treat those symptoms and thedisorders. The present invention further provides such tDCS therapywhile the subject sleeps in order to minimize the time required andimpact of the therapy on the subject's waking life. The system, methods,and devices of the present invention are intended to provide a low-doseelectrical current, trans-cranially, to a specific area of the subject'sbrain while he or she sleeps in order to decrease the occurrence,severity, and duration of the symptoms of movement and/or sleepdisorders. The present invention aims to reduce the amount of medicationnecessary, counteract the effects of medication wearing off duringsleep, and to overall improve the quality of life of subjects sufferingfrom movement disorders.

Preferably, the system or monitor is constructed to be rugged, so as towithstand transport, handling and to reliably survive daily use by thesubject. The system or monitor should preferably be splash-proof (orwater tight), dust-tight, scratch-resistant, and resistant to mechanicalshock and vibration. The system or monitor should preferably be portableso the subject may travel with the device as necessary.

The system or monitor should preferably be capable of non-expert use. Bythis, it is meant that a person should not be required to possessextraordinary or extensive special medical training in order to use thesystem effectively and reliably. The system should therefore preferablybe user-friendly in operation in a number of respects. First, the systemshould be capable of easy donning and doffing, substantially error-proofalignment and placement of the device on the subject's head. Second, thesystem should preferably have automatic detection of input signalquality; for example, the system should be capable of detecting animbalance in electrode impedances, physiological and environmentalartifacts, and electrical interferences and noise. Third, the systemshould preferably be capable of automatically detecting the subject'sstate or level of consciousness. Fourth, the system should preferably becapable of automatically providing a therapeutic direct current to thesubject's brain without the need for user interaction.

Preferably, the system should operate in real time. One example ofreal-time operation is the ability of the system to detect the subject'slevel of consciousness and implement a current control protocolaccordingly. Another example of real-time operation is the ability ofthe system to detect an improper or faulty connection, position, orsignal of an electrode and cease providing a direct electrical currentto that electrode or all electrodes. The system described in thisinvention also preferably incorporates a number of unique features thatimprove safety, performance, durability, and reliability. The systemshould be limited in the level or strength of the current that may besupplied to the subject. The placement of the electrodes should bereadily ascertainable, repeatable, and not easily moved once in place.Integrated impedance sensors will automatically stop stimulation if thedevice is removed from the head.

All embodiments of the present invention include a wearable device to beplaced on the subject's head while he or she sleeps. In someembodiments, the wearable device will be custom fitted to each subjectto ensure proper electrode placement. In other embodiments, the wearabledevice will comprise a small patch-like apparatus which can be placed onthe subject's head before sleep and discarded upon awaking.

As the subject sleeps, painless tDCS will be provided at specifiedintervals. In order to provide the necessary current, all embodiments ofthe present invention will include a current generation device. Thecurrent generation device should be capable of providing a directcurrent over a period of time with little or no variation in thecurrent.

Many embodiments of the brain function monitor comprise an electrodelead or electrode array. At least one electrode may be utilized, and insuch embodiment, the electrode is a typical tDCS electrode known tothose in the art. More preferably, at least two electrodes may beutilized: at least one for injection of the direct current, and at leastone for return of the direct current. Even more preferably, at least 5electrodes are used. In the five electrode array, at least one electrodeis used to deliver the current, and at least 4 electrodes are presentfor return of the current from the subject's brain. Other electrodearrangements, configurations, and placements are also contemplated foruse with the system.

The system will not be designed to replace PD medication but rather willaugment therapy and may result in a reduction of required medicationuse. Since subjects often feel worst in the morning after medicationfrom the previous day has worn off, stimulation during the night mayhelp subjects wake up feeling better. Additionally, designing the devicefor overnight use will make the system convenient and accessible sosubjects need not worry about using the device in public or during theirdaily activities. Development will focus on treating the motor symptomsof PD; however, the proposed system may prove beneficial for overallsleep quality or other PD-related sleep disorders.

One embodiment of the present invention includes a method of providingtherapy for movement disorder symptoms comprising steps of providing awearable apparatus comprising at least two surface scalp electrodes, atleast one electrode for providing a low dose direct electrical currentto the patient, and at least one electrode for return of the low dosedirect electrical current, placing the apparatus on a subject's head andhaving the subject wear the apparatus during sleep, and providing a lowdose direct electrical current from the at least one surface scalpelectrode for providing a low dose direct electrical current across thesubject's cranium to stimulate at least one area of the subject's brainat a pre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement disordersymptoms, wherein cortex modulation in frontal regions, contralateralmotor regions, and occipital lobe of the subject's brain is minimized tobe less than 0.01 V/m.

Another embodiment of the present invention includes method of providingtherapy for movement disorder symptoms comprising steps of providing awearable apparatus, providing an array of at least five surface scalpelectrodes, at least one central anodal electrode surrounded by at leastfour return electrodes arranged in a ring around the anodal electrode,affixing or embedding the electrode array to the wearable apparatus,placing the apparatus on a subject's head and having the subject wearthe apparatus during sleep, and providing a low dose direct electricalcurrent from the at least one anodal electrode across the subject'scranium to stimulate at least one area of the subject's brain at apre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement disordersymptoms, wherein the low dose electrical current is provided at 2milli-amps (mA).

Yet another embodiment of the present invention includes a method ofproviding therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, providing an array of at least fivesurface scalp electrodes, at least one central anodal electrodesurrounded by at least four return electrodes arranged in a ring aroundthe anodal electrode, affixing or embedding the electrode array to thewearable apparatus, placing the apparatus on a subject's head and havingthe subject wear the apparatus during sleep, and providing a low dosedirect electrical current from the at least one anodal electrode acrossthe subject's cranium to stimulate at least one area of the subject'sbrain at a pre-determined duty-cycle, the area of the subject's brainbeing stimulated corresponding to at least one symptom of a movementdisorder to reduce the occurrence, severity, and/or duration of movementdisorder symptoms, wherein the low dose electrical current is providedat 2 milli-amps (mA), and a 33% duty cycle.

Still another embodiment of the present invention includes a method ofproviding therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, inserting, attaching to, affixing to, orembedding in the wearable apparatus an array of at least five surfacescalp electrodes, at least one central anodal electrode surrounded by atleast four return electrodes arranged in a ring around the anodalelectrode, placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep, and providing a low dose directelectrical current from the at least one anodal electrode across thesubject's cranium to stimulate at least one area of the subject's brainat a pre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement disordersymptoms, wherein the low dose electrical current is provided at 2milli-amps (mA).

Still yet another embodiment of the present invention includes amovement disorder therapy device comprising a wearable apparatus capableof being worn about a subject's head, at least two surface scalpelectrodes affixed to or embedded in the wearable, at least oneelectrode for providing a low dose direct electrical current to thepatient, and at least one electrode for return of the low dose directelectrical current, a processor comprising a stimulation control programfor controlling how the low dose electrical current is provided to thepatient, and a current generator for providing a low-dose (low current)electrical stimulation impulse through the at least one electrode forproviding a low dose direct electrical current to the patient, whereinthe current generator is capable of providing a steady, constant currentat a predetermined duty cycle.

Even yet another embodiment of the present invention includes a movementdisorder therapy device comprising a wearable apparatus capable of beingworn about a subject's head, an array of at least five surface scalpelectrodes, at least one central anodal electrode surrounded by at leastfour return electrodes arranged in a ring around the anodal electrode, aprocessor comprising a stimulation control program for controlling howthe low dose electrical current is provided to the patient, and acurrent generator for providing a low-dose (low current) electricalstimulation impulse through the at least one electrode for providing alow dose direct electrical current to the patient, wherein the currentgenerator is capable of providing a steady, constant current at apredetermined duty cycle.

Still another embodiment of the present invention includes a movementdisorder therapy device comprising a wearable apparatus capable of beingworn about a subject's head, an array of at least five surface scalpelectrodes, at least one central anodal electrode surrounded by at leastfour return electrodes arranged in a ring around the anodal electrode, aprocessor comprising a stimulation control program for controlling howthe low dose electrical current is provided to the patient, and acurrent generator for providing a low-dose (low current) electricalstimulation impulse through the at least one electrode for providing alow dose direct electrical current to the patient, wherein the currentgenerator is capable of providing a steady, constant current at apredetermined 33% duty cycle.

Yet another embodiment of the present invention includes a movementdisorder therapy device comprising a harness to be worn about asubject's head, an electrode array comprising at least five surfacescalp electrodes, at least one anodal electrode for delivering a lowdose constant electrical current and at least for return electrodes forthe current to exit the subject, and a current generator wherein thesurface area of each the electrodes in contact with the subject's skinis 8 mm or less, and wherein the current generator is capable ofsupplying a constant current according to a predetermined 50% dutycycle.

Even still yet another embodiment of the present invention includes amethod of providing therapy for movement disorder symptoms comprisingsteps of placing an apparatus comprising a flexible harness and an arrayof at least 5 surface scalp electrodes, at least one electrode, applyinga constant direct current at about 2 mA (milli-amps) transcranially to asubject's brain at a 33% duty cycle, wherein the current is active forat least thirty (30) minutes continuously during each cycle, and whereinthe apparatus is placed on the subject's head in a manner to align theelectrodes to deliver the current to a portion of the subject's braincorresponding to a desired movement disorder symptom to be treated.

Still even yet another embodiment of the present invention includes amethod of providing therapy for movement disorder symptoms comprisingsteps of providing a wearable apparatus, providing an array of at leastfive surface scalp electrodes, at least one central anodal electrodesurrounded by at least four return electrodes arranged in a ring aroundthe anodal electrode, affixing or embedding the electrode array to thewearable apparatus, placing the apparatus on a subject's head and havingthe subject wear the apparatus during sleep, checking the electricalimpedance of each of the at least five electrodes, and providing a lowdose direct electrical current from the at least one anodal electrodeacross the subject's cranium to stimulate at least one area of thesubject's brain at a pre-determined duty-cycle, the area of thesubject's brain being stimulated corresponding to at least one symptomof a movement disorder to reduce the occurrence, severity, and/orduration of movement disorder symptoms, wherein the low dose electricalcurrent is provided at about 2 milli-amps (mA).

Yet another embodiment of the present invention includes a method ofproviding therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, providing a wearable apparatuscomprising at least two surface scalp electrodes, at least one electrodefor providing a low dose direct electrical current to the patient, andat least one electrode for return of the low dose direct electricalcurrent, affixing or embedding the electrode array to the wearableapparatus, placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep, checking the electricalimpedance of each of the at least five electrodes, and providing a lowdose direct electrical current from the at least one surface scalpelectrode for providing a low dose direct electrical current across thesubject's cranium to stimulate at least one area of the subject's brainat a pre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement disordersymptoms, wherein the low dose electrical current is provided at about 2milli-amps (mA).

Even still yet another embodiment of the present invention includes amethod of providing therapy for movement disorder symptoms comprisingsteps of custom fitting a wearable apparatus to fit a subject's head,providing an array of at least five surface scalp electrodes, at leastone central anodal electrode surrounded by at least four returnelectrodes arranged in a ring around the anodal electrode, affixing orembedding the electrode array to the custom-fitted wearable apparatus,placing the apparatus on a subject's head and having the subject wearthe apparatus during sleep, checking the electrical impedance of each ofthe at least five electrodes, and providing a low dose direct electricalcurrent from the at least one surface scalp electrode for providing alow dose direct electrical current across the subject's cranium tostimulate at least one area of the subject's brain at a pre-determinedduty-cycle, the area of the subject's brain being stimulatedcorresponding to at least one symptom of a movement disorder to reducethe occurrence, severity, and/or duration of movement disorder symptoms.

Even still another embodiment of the present invention includes a methodof providing therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, providing an array of at least fivesurface scalp electrodes, at least one central anodal electrodesurrounded by at least four return electrodes arranged in a ring aroundthe anodal electrode, affixing or embedding the electrode array to thewearable apparatus, placing the apparatus on a subject's head and havingthe subject wear the apparatus during sleep, determining the subject'ssleep stage substantially in real time, and providing a low dose directelectrical current from the at least one anodal electrode across thesubject's cranium to stimulate at least one area of the subject's brainat a pre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement and/orsleep disorder symptoms, wherein the duty cycle for providing the lowdose direct electrical current is turned on based at least in part onthe determined sleep stage.

Still even another embodiment of the present invention includes a methodof providing therapy for movement disorder symptoms comprising steps ofcustom fitting a wearable apparatus to fit a subject's head, providingan array of at least five surface scalp electrodes, at least one centralanodal electrode surrounded by at least four return electrodes arrangedin a ring around the anodal electrode, affixing or embedding theelectrode array to the custom-fitted wearable apparatus, placing theapparatus on a subject's head and having the subject wear the apparatusduring sleep, determining the subject's sleep stage substantially inreal time, and providing a low dose direct electrical current from theat least one anodal electrode across the subject's cranium to stimulateat least one area of the subject's brain at a pre-determined duty-cycle,the area of the subject's brain being stimulated corresponding to atleast one symptom of a movement disorder to reduce the occurrence,severity, and/or duration of movement and/or sleep disorder symptoms,wherein the duty cycle for providing the low dose direct electricalcurrent is turned on based at least in part on the determined sleepstage.

Yet still another embodiment of the present invention includes a methodof providing therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, providing a wearable apparatuscomprising at least two surface scalp electrodes, at least one electrodefor providing a low dose direct electrical current to the patient, andat least one electrode for return of the low dose direct electricalcurrent, affixing or embedding the electrode array to the wearableapparatus, placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep, determining the subject's sleepstage substantially in real time, and providing a low dose directelectrical current from the at least one anodal electrode across thesubject's cranium to stimulate at least one area of the subject's brainat a pre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement and/orsleep disorder symptoms, wherein the duty cycle for providing the lowdose direct electrical current is turned on based at least in part onthe determined sleep stage.

Still even yet another embodiment of the present invention includes amethod of providing therapy for movement disorder symptoms comprisingsteps of providing a wearable apparatus, providing an array of at leastfive surface scalp electrodes, at least one central anodal electrodesurrounded by at least four return electrodes arranged in a ring aroundthe anodal electrode, affixing or embedding the electrode array to thewearable apparatus, placing the apparatus on a subject's head and havingthe subject wear the apparatus during sleep, checking the electricalimpedance of each of the at least five electrodes, determining thesubject's sleep stage substantially in real time, and providing a lowdose direct electrical current from the at least one anodal electrodeacross the subject's cranium to stimulate at least one area of thesubject's brain at a pre-determined duty-cycle, the area of thesubject's brain being stimulated corresponding to at least one symptomof a movement disorder to reduce the occurrence, severity, and/orduration of movement and/or sleep disorder symptoms, wherein the dutycycle for providing the low dose direct electrical current is turned onbased at least in part on the determined sleep stage.

Yet another embodiment of the present invention includes a method ofproviding therapy for movement disorder symptoms comprising steps ofproviding a wearable apparatus, providing a wearable apparatuscomprising at least two surface scalp electrodes, at least one electrodefor providing a low dose direct electrical current to the patient, andat least one electrode for return of the low dose direct electricalcurrent, affixing or embedding the electrode array to the wearableapparatus, placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep, checking the electricalimpedance of each of the at least five electrodes, determining thesubject's sleep stage substantially in real time, and providing a lowdose direct electrical current from the at least one anodal electrodeacross the subject's cranium to stimulate at least one area of thesubject's brain at a pre-determined duty-cycle, the area of thesubject's brain being stimulated corresponding to at least one symptomof a movement disorder to reduce the occurrence, severity, and/orduration of movement and/or sleep disorder symptoms, wherein the dutycycle for providing the low dose direct electrical current is turned onbased at least in part on the determined sleep stage.

Additional features and advantages of the invention will be set forth inthe detailed description which follows, and in part will be readilyapparent to those skilled in the art from that description or recognizedby practicing the invention as described herein, including the detaileddescription which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description are merely exemplary of theinvention, and are intended to provide an overview or framework forunderstanding the nature and character of the invention as it isclaimed. It is understood that many other embodiments of the inventionare not directly set forth in this application but are none the lessunderstood to be incorporated by this application. The accompanyingdrawings are included to provide a further understanding of theinvention, and are incorporated in and constitute a part of thisspecification. The drawings illustrate various embodiments of theinvention and together with the description serve to explain theprinciples and operation of the many embodiments of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a subject wearing one embodiment of the inventionand receiving tDCS therapeutic treatment while asleep.

FIG. 2 is a diagram of one embodiment of the present inventioncomprising a custom-fitted head-worn wearable apparatus with a 4×1electrode array affixed to or embedded into the wearable.

FIG. 3 is a flow chart depicting one embodiment of a method of thepresent invention whereby cortical modulation is minimized during tDCStherapy.

FIG. 4 is a flow chart depicting another embodiment of a method of thepresent invention whereby at least 5 electrodes are provided in an arrayand tDCS therapy is provided with an electrical current of 2 milli-amps(mA).

FIG. 5 is a flow chart of another embodiment of a method of the presentinvention including the step of attaching an array of at least 5electrodes to a wearable apparatus to place on the subject's head, andthen providing a therapeutic tDCS current of 2 mA.

FIG. 6 is a flow chat of yet another embodiment of a method of thepresent invention whereby an apparatus comprising at least 5 electrodesin an array is provided and a tDCS therapeutic current is applied at 2mA for a minimum of 30 minutes continuously.

FIG. 7 is a flow chart of still another embodiment of a method of thepresent invention whereby an array of at least 5 electrodes is providedand the electrical impedance of each the at least two electrodes ischecked in order to ensure a strong, proper connection between theelectrodes and the subject's scalp.

FIG. 8 is a flow chart of still yet another embodiment of a method ofthe present invention whereby at least two electrodes are provided andthe electrical impedance of the at least 2 electrode array is checked inorder to ensure a strong, proper connection between the electrodes andthe subject's scalp.

FIG. 9 is a flow chart of still another embodiment of a method of thepresent invention whereby wearable is custom-fitted to a particularsubject's head, an array of at least 5 electrodes is provided and theelectrical impedance of each the at least two electrodes is checked inorder to ensure a strong, proper connection between the electrodes andthe subject's scalp.

FIG. 10 is a flow chart of another embodiment of a method of the presentinvention including the step of attaching an array of at least 5electrodes to a wearable apparatus to place on the subject's head,determining the stage of sleep the subject is in, and then starting toprovide a therapeutic tDCS current based on the determined sleep stage.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a system and methods for noninvasivelyproviding therapy for movement disorder symptoms. Movement disorders,for the purposes of this invention, include, but are not limited to,Parkinson's Disease and Parkinsonism, Dystonia, Cerebral Palsy, Choreaand dyskinesias in general, Huntington's Disease, Ataxia, Tremor andEssential Tremor, Myoclonus, tics, Tourette Syndrome, Restless LegSyndrome, Stiff Person Syndrome, gait disorders, sleep disturbances, andthe like. The present invention provides such a therapy system whichprovides trans-cranial direct current stimulation (tDCS) in order totreat those symptoms and the disorders. The present invention furtherprovides such tDCS therapy while the subject sleeps in order to minimizethe time required and impact of the therapy on the subject's wakinglife. The system, methods, and devices of the present invention areintended to provide a low-dose electrical current, trans-cranially, to aspecific area of the subject's brain while he or she sleeps in order todecrease the occurrence, severity, and duration of the symptoms ofmovement disorders. The present invention aims to reduce the amount ofmedication necessary, counteract the effects of medication wearing offduring sleep, and to overall improve the quality of life of subjectssuffering from movement disorders.

For the present invention the subject who is receiving therapy formovement disorder symptoms can be any type of animal, preferably amammal, most preferably a human. The subjects for whom the device isutilized are identified by a diagnosis of a movement disorder andexhibiting of symptoms thereof. The device and methods are designed tobe used and performed, respectively, largely by untrained or minimallytrained personnel, and most preferably by the subject himself or herselfwith very little instruction, and no formal education required.

The devices and methods of the present invention are designed to be usedand performed at home. The present invention is designed so as thesubject or patient can use the devices and methods with no formaltraining or education, and with little or no special training required.The present invention is preferably used by the subject or patientoutside of a clinical setting. The present invention is designed to besmall, lightweight, portable, and rugged, and thus capable of being usedin the subject's home or while travelling. Many embodiments of thepresent invention involve the subject or patient using the devices andmethods during sleep, thus the system is specifically designed to beused daily in the subject's or patient's normal course of life withoutrequiring bulky, cumbersome equipment, special facilities, or access tomedical personnel.

The system preferably operates substantially in real time. By real-time,it is intended that the system acquires any signals and makes anyrequired calculations or determinations based on those signals in lessthan 5 minutes. More preferably, the system performs these functions inless than 3 minutes. Even more preferably, the system performs thesefunctions in less than 1 minute. Still more preferably, the systemperforms these functions in less than 45 seconds. Yet more preferably,the system performs these functions in less than 30 seconds. Even stillmore preferably, the system performs these functions in less than 20seconds. Still yet more preferably, the system performs these functionsin less than 10 seconds. Even still yet more preferably, the systemperforms these functions in less than 5 seconds. Most preferably, thesystem performs these functions substantially simultaneously.

Various embodiments of the methods of the present invention include oneor more of the following steps, and variations thereof. These stepsinclude, but are not limited to, providing a wearable apparatuscomprising at least two surface scalp electrodes, at least one electrodefor providing a low dose direct electrical current to the subject, andat least one electrode for return of the low dose direct electricalcurrent, placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep, and providing a low dose directelectrical current from the at least one surface scalp electrode forproviding a low dose direct electrical current across the subject'scranium to stimulate at least one area of the subject's brain at apre-determined duty-cycle, the area of the subject's brain beingstimulated corresponding to at least one symptom of a movement disorderto reduce the occurrence, severity, and/or duration of movement disordersymptoms.

Similarly, various embodiments of the present invention include one ormore of the following components, and variations thereof. Thesecomponents include, but are not limited to, a wearable apparatus capableof being worn about a subject's head, at least two surface scalpelectrodes affixed to or embedded in the wearable, at least oneelectrode for providing a low dose direct electrical current to thesubject, and at least one electrode for return of the low dose directelectrical current, an array of at least five surface scalp electrodes,at least one central anodal electrode surrounded by at least four returnelectrodes arranged in a ring around the anodal electrode, a processorcomprising a stimulation control program for controlling how the lowdose electrical current is provided to the subject, and a currentgenerator for providing a low-dose (low current) electrical stimulationimpulse through the at least one electrode for providing a low dosedirect electrical current to the subject.

The first step in utilizing all embodiments of the present invention isidentifying a subject or patient for whom tDCS therapy would bebeneficial. Subjects or patients who are or have been experiencingsymptoms of movement disorders, or who have been diagnosed with amovement disorder may be selected to use the present invention's devicesand methods. Additionally, subjects or patients with symptoms ordiagnoses of some mental health disorders (e.g., depression, anxietydisorders, schizophrenia, obsessive compulsive disorder, and the like),or other disorders (e.g., tinnitus, fibromyalgia, speech difficulties,memory and cognitive issues, and the like), would be valid candidatesfor using the present invention. Typical movement disorders and symptomssought to be treated by the present invention include, but are notlimited to, Parkinson's Disease and Parkinsonism (characterized byshaking, rigidity, slow movement, gait disturbances, cognitive andbehavioral decline, sleep disturbances, etc.), Dystonia (sustainedmuscle contractions and torsion), Cerebral Palsy (characterized byabnormal muscle tone, abnormal reflexes, motor coordination decline,spasms and involuntary movements, gait and balance issues, etc.),Bradykinesia (slowness of movement), Chorea and dyskinesias in general(characterized by rapid, involuntary movements of the body),Huntington's Disease (characterized by lack of coordination,dyskinesias, rigidity, loss of cognitive capacity, and the likedepending on the disease's progression), Ataxia (gross lack ofcoordination), Tremor and Essential Tremor (involuntary musclecontraction and relaxing), Myoclonus (brief, involuntary muscletwitching), tics (motor and phonic tics), Tourette Syndrome(characterized by multiple motor tics and phonic tic(s)), Restless LegSyndrome (irresistible urge to move the body to do uncomfortablesensations), Stiff Person Syndrome (progressive rigidity and stiffness,spasms), gait disorders, sleep disturbances (as a result of some othermovement or mental health disorder), and the like. The symptoms for manyof the above disorders, particularly the movement disorders, tend tooverlap between disorders, and often stand alone as their own disorder(e.g., Bradykinesia). Subjects or patients who experience any of theabove or similar symptoms, or are diagnosed with any of these, orsimilar disorders, can be selected as viable beneficiaries of tDCStherapy. Further, subjects who are currently on medication for one ormore of the symptoms or disorders may benefit from tDCS therapy. Somepreferred embodiments of the present invention are aimed at treatingsubjects with symptoms and/or diagnoses of movement disorders, such asParkinson's Disease, Tremor and Essential Tremor, Huntington's Disease,and the like.

All embodiments of the present invention are designed to help improvethe subject's quality of life by reducing the occurrence, severity,and/or duration of the symptoms of his or her particular disorder(s).Improvement should be measured by each individual symptom as a singlesubject may exhibit multiple symptoms from a single or multipledisorders. Improvement may be measured as a reduction in the particularsymptom (e.g., % reduction in the occurrence of dyskinesias), or by theincrease in subject's functionality (e.g., % increase in motor responsetime). The nature of tDCS therapy typically requires individual symptomsto be treated separately, as each symptom is typically controlled ortriggered by a different part of the brain. The subject and his or herphysician typically, during the screening process, determine whichsymptom(s) are the most troublesome to the subject's life and design thetherapy to treat those symptoms. Regardless of which symptom(s) arebeing treated (i.e., motor/physical symptoms or mental health symptoms),the present invention is designed to improve the subject's quality oflife by reducing the occurrence, severity, and/or duration of symptoms.Preferably, the subject experiences at least a 3% improvement in symptomoccurrence, severity, and/or duration. More preferably, the subjectexperiences at least a 5% improvement in symptom occurrence, severity,and/or duration. Still more preferably, the subject experiences at leasta 10% improvement in symptom occurrence, severity, and/or duration. Yetmore preferably, the subject experiences at least a 13% improvement insymptom occurrence, severity, and/or duration. Even more preferably, thesubject experiences at least a 15% improvement in symptom occurrence,severity, and/or duration. Even still more preferably, the subjectexperiences at least a 20% improvement in symptom occurrence, severity,and/or duration. Still yet more preferably, the subject experiences atleast a 23% improvement in symptom occurrence, severity, and/orduration. Even yet more preferably, the subject experiences at least a25% improvement in symptom occurrence, severity, and/or duration. Stilleven more preferably, the subject experiences at least a 27% improvementin symptom occurrence, severity, and/or duration. Even still yet morepreferably, the subject experiences at least a 30% improvement insymptom occurrence, severity, and/or duration. Most preferably, thesubject experiences a greater than 35% improvement in symptomoccurrence, severity, and/or duration.

Improvement in symptoms, particularly for movement disorders, and evenmore particularly for Parkinson's Disease and its associated symptoms,may be quantitatively measured by means of a reduction in symptomscoring according to scoring methods and systems known to those in theart. Examples of such scoring systems include the UPDRS, MDS-UPDRS.Another such scoring method for quantifying movement disorder symptoms,similar to these two systems, is presented in U.S. patent applicationSer. No. 13/152,963, which is herein incorporated by reference. Thesesystems for scoring movement disorder symptoms provide a score thatrelates to the severity of the symptom. Typically, the higher the score,the more severe the symptom. If UPDRS or MDS-UPDRS scores are used, aclinician typically monitors the progression of the symptoms. However,the system in application Ser. No. 13/152,963 allows for automated orsemi-automated scoring at home. That system can be utilized with thepresent invention to quantify symptoms, treat them with tDCS therapy,and track the progression or improvement of those symptoms. Regardlessof the scoring method that is actually used, the present invention aimsto provide an improvement in the subject's or patient's symptoms asmeasured by one of these scoring systems. The UPDRS is, at the time ofthis application, the most commonly known and used scoring system, and,therefore preferably, the subject experiences at least a 10% reductionin UPDRS score for at least one symptom. More preferably, the subjectexperiences at least a 20% reduction in UPDRS score for at least onesymptom. Still more preferably, the subject experiences a 30% reductionin UPDRS score for at least one symptom. Yet more preferably, thesubject experiences at least a 40% reduction in UPDRS score for at leastone symptom. Even more preferably, the subject experiences at least a50% reduction in UPDRS score for at least one symptom. Still yet morepreferably, the subject experiences at least a 60% reduction in UPDRSscore for at least one symptom. Even yet more preferably, the subjectexperiences at least a 70% reduction in UPDRS score for at least onesymptom. Even yet more preferably, the subject experiences at least a80% reduction in UPDRS score for at least one symptom. Even still yetmore preferably, the subject experiences a at least 90% reduction inUPDRS score for at least one symptom.

Recent studies have shown that tDCS therapy shows noticeable improvementin movement disorder symptoms when compared to sham stimulation. SeeDavid H. Benninger et al. Transcranial Direct Current Stimulation forthe Treatment of Parkinson's Desease, 81 J. NEUROL. NEUROSURG.PSYCHIATRY 1105 (2011); see also Felipe Fregni, MD, PhD et al.,Noninvasive Cortical Stimulation with Transcranial Direct CurrentStimulation in Parkinson's Disease, 21 MOVEMENT DISORDERS 1693 (2006).Sham stimulation is a control condition wherein a brief electricalimpulse is delivered to the subject to imitate the initiation of tDCStherapy, but the current is then shut off for the rest of thestimulation time. By using tDCS, it is possible to show measurable,significant improvement in individual movement disorder symptoms.

For gait abnormalities or disturbances, the more often, severe, orlength the disturbance, the longer it takes the subject to walk a givendistance. Thus, one way to measure improvement in gait disturbances isby showing a decrease in walking time over a given distance. By usingthe present invention to treat gait abnormalities or disturbances,preferably the subject experiences at least a 15% decrease in walkingtime. More preferably, the subject experiences at least a 20% decreasein walking time. Yet more preferably, the subject experiences at least a25% decrease in walking time. Still more preferably, the subjectexperiences at least a 30% decrease in walking time. Even morepreferably, the subject experiences at least a 35% decrease in walkingtime. Still yet more preferably, the subject experiences at least a 40%decrease in walking time. Even yet more preferably, the subjectexperiences at least a 45% decrease in walking time. Even still morepreferably, the subject experiences a greater than 50% decrease inwalking time.

For bradykinesia, or slowness of movement, improvement can be shown bymeasuring the length of time it takes for the subject to complete aseries of sequential movements, and having that sequential movement timedecrease. By using the present invention to treat bradykinesia,preferably the subject experiences at least a 25% decrease in sequentialmovement time. More preferably, the subject experiences at least a 30%decrease in sequential movement time. Yet more preferably, the subjectexperiences at least a 35% decrease in sequential movement time. Stillmore preferably, the subject experiences at least a 40% decrease insequential movement time. Even more preferably, the subject experiencesat least a 45% decrease in sequential movement time. Still yet morepreferably, the subject experiences at least a 50% decrease insequential movement time. Even still more preferably, the subjectexperiences at least a 55% decrease in sequential movement time. Evenyet more preferably, the subject experiences a greater than 60% decreasein sequential movement time.

Improvement in tremor and Essential tremor, the involuntary contractionand relaxing of muscles appearing as oscillations or twitching of thesubject's body, particularly the extremities, can be measured orquantified by a reduction the frequency (number of oscillations ortwitches per second) of the tremor. This is not the same as how oftentremor occurs, but rather an actual measurement of the tremor when itdoes occur. Essentially, improvement in tremor appears as a slowing ofthe oscillations or twitches, with the aim of reducing the frequencyenough to allow the subject to feel and appear still and steady. Throughusing the present invention, the subject preferably experiences at leasta 10% reduction in the tremor frequency. More preferably, the subjectpreferably experiences at least a 20% reduction in the tremor frequency.Yet more preferably, the subject preferably experiences at least a 30%reduction in the tremor frequency. Still more preferably, the subjectpreferably experiences at least a 40% reduction in the tremor frequency.Even more preferably, the subject preferably experiences at least a 50%reduction in the tremor frequency. Still yet more preferably, thesubject preferably experiences at least a 60% reduction in the tremorfrequency. Even yet more preferably, the subject preferably experiencesat least a 70% reduction in the tremor frequency. Even still morepreferably, the subject preferably experiences at least a 80% reductionin the tremor frequency. Even still yet more preferably, the subjectpreferably experiences a greater than 90% reduction in the tremorfrequency.

The step of providing a wearable apparatus comprising at least twosurface scalp electrodes, at least one electrode for providing a lowdose direct electrical current to the subject, and at least oneelectrode for return of the low dose direct electrical current is thefirst step in many method embodiments of the present invention. In orderto provide therapy to a subject via tDCS, the appropriate mechanismand/or apparatus must be applied to the subject's head. The presentinvention may utilize various forms of this wearable apparatus invarious embodiments. Preferably, the wearable apparatus is designed tobe flexible, easy to don and doff, and disposable yet still resilientand capable of withstanding forces common in daily wear, wear duringsleep, and even emergency settings. In some embodiments, the wearablemay be a custom fitted wearable that is molded, formed, or otherwiseconstructed to individually fit each specific subject. The custom fittedwearable allows for easy, repeatable placement of the electrodes(described in greater detail below) in the proper location(s). Inembodiments where the wearable device is a custom-molded head-wornapparatus, the apparatus itself should be capable of being worn dailyfor a long period of time (on the order of years), without being damagedor worn out. Further, in such custom molded embodiments, the electrodesor array(s) may be affixed to or embedded into the wearable apparatus bythe subject before donning the head worn apparatus, and discarded eachmorning, or replaced periodically. Alternatively, the wearable apparatusmay be non-custom fitted in the sense that it may be of a uniform size,shape, and/or configuration for all subjects. In such embodiments, thepatient is preferably trained or otherwise instructed on the propermethod and location of placing the wearable to ensure the electrodes arein the proper location and configuration to provide the therapy.

The wearable being provided may be constructed of any material known tothose of skill in the art. Preferably, the wearable is designed andconstructed to be durable, resilient, flexible, and easy to clean. Theapparatus may be secured about the subject's head by means commonlyknown to those in the art, including, but not limited to, a cap or othergarment completely encompassing the subject's head, a strap that issecured by compression or elastic means, or may utilize common fasteningmethods such as hook-and-loop, belt-type, snap connectors, or the like.Additionally, or in conjunction with one of the above means, an adhesivelayer may be used with a wearable apparatus to further ensure a stable,secure placement of the electrode lead or array. In embodiments wherethe electrodes are affixed to or embedded in a disposable patch-likewearable, the adhesive layer is particularly important to maintainsecure, stable placement of the electrodes on the subject's head. In apreferred embodiment, the head-worn apparatus is a custom molded capthat fits snugly but comfortably about the subject's head, and iscapable of maintaining a secure placement with minimal shifting, drift,or other movement of the apparatus, for the entire length of timenecessary for monitoring. The adhesive layer is also preferably capableof providing a secure, stable attachment to the subject in the presenceof dirt, sweat, and other detritus which may be covering the subject'sskin during application, without the need for washing, cleaning orotherwise preparing the area of application.

The step of placing the apparatus on a subject's head and having thesubject wear the apparatus during sleep refers to a preferred embodimentwherein the patient wears the device and receives tDCS therapy duringsleep. The wearable is preferably applied to the subject's head in amanner such that the electrodes come into contact with the subject'sskin. The wearable is placed onto the subject's head, and is thensecured by virtue of one of the above listed, or similar means, in orderto ensure secure, stable positioning of the wearable and thus theelectrodes during use. Preferably, the location where the electrodescome in contact with the subject's skin checked and found to be freefrom cuts, lesions, skin disease, and other skin irritations which canimpair the connection and attachment of the electrodes to the subject'sskin.

In some embodiments, including a preferred embodiment, the systempreferably includes a step of measuring electrical impedance of theelectrodes. Impedance checking is used to ensure that the electrodeshave good contact with the subject's skin. Good electrode-skin contactensures accurate, efficient delivery of the tDCS current, and thusmaximizes the effectiveness of the therapy. Impedance checking can bedone in several ways.

The system may perform electrical impedance checking by any methodcurrently known to those in the art or later developed. One such methodof electrode impedance measurement involves calculating the electricalimpedance value by measuring a voltage across two electrodes. The twoelectrodes may each be signal measurement or current delivery electrodes(again, the electrodes are described in greater detail below), or may bea measurement or delivery electrode and a reference or return electrode.Impedance is the complex form of electrical resistance, that is,impedance is the electrical resistance to sinusoidal alternating current(AC). Impedance values take on a complex form containing both amagnitude as well as a phase, which indicates the lag between thecurrent and voltage. Impedance can be calculated as a function of boththe magnitudes and the phases of the voltage, current, and impedance. Invarious embodiments of the present invention, the calculation is verysimilar to traditional Ohm's law and calculates impedance by dividingthe measured voltage by the known current. The phase component describesthe fraction of the lagging wave that has been completed by the when itreaches the same reference point as the first signal, in the presentcase that reference point is the electrode. The calculation of anelectrode's impedance involves supplying an electrical current to theelectrode at a known frequency and amplitude, and measuring the voltageacross that electrode and another electrode. In the first step, anelectrical current is supplied to the first electrode. Once the currentis being applied at the known frequency and amplitude, the system isable to take the required voltage measurement across thecurrent-supplied electrode and another electrode, and calculate theimpedance of that electrode to which the current is applied. Thereafter,the process is repeated for the other electrodes to get impedancemeasurements for each of them. Some embodiments may involvesimultaneously supplying a current at a known amplitude and frequency totwo electrodes, and measuring the voltage, thus providing a totalimpedance for the two electrodes combined. In such embodiments, thefirst electrode's calculated impedance is subtracted from the totalimpedance of the two electrodes to obtain the second electrode'simpedance value. In many other embodiments; however, the impedancevalues are measured individually for each electrode by supplying acurrent to each electrode in turn, as described above. In embodimentsutilizing an electrode array, such as the previously described 4×1array, the electrodes in each array are typically and preferablyemployed as a single electrode, or rather a single device. In suchembodiments, the electrodes may be individually addressable, but aremore often a single passive device wherein there is a single anodalelectrode and the cathode is divided into separate parts, for example 4parts in the 4×1 array. For purposes of the electrode impedancemeasurement described above with electrode array embodiments, when twoelectrodes are used, typically, such impedance measurements areperformed between and/or among two separate arrays, and not betweenand/or amongst individual electrodes in a single array.

Given the nature of tDCS therapy as applied by the current invention, apreferred embodiment involves carrying out the above impedancemeasurement process during the period of the duty cycle in which notherapeutic current is applied to the subject. This allows thetherapeutic current to be applied for the entire desired period withoutinterruption to measure electrode impedance. In order to ensure thatelectrode impedance is as low as possible, and thus the connectionbetween the electrodes and the subject's skin is as strong as possible,the impedance measurement is preferably taken as close in time to theduty cycle on-period as possible. That is, preferably, the electrodeimpedance measurement is taken less than 10 minutes before thetherapeutic tDCS current is turned on. More preferably, the electrodeimpedance measurement is taken less than 8 minutes before thetherapeutic tDCS current is turned on. Still more preferably, theelectrode impedance measurement is taken less than 6 minutes before thetherapeutic tDCS current is turned on. Even more preferably, theelectrode impedance measurement is taken less than 4 minutes before thetherapeutic tDCS current is turned on. Yet more preferably, theelectrode impedance measurement is taken less than 2 minutes before thetherapeutic tDCS current is turned on. In the event that the impedancemeasurement of an electrode is too high, the system may provide awarning to the subject to wake up and replace the electrode, may alertanother person to change the electrode, may divert the current away fromthat electrode and only using the remaining electrodes, and/or may haltthe duty cycle on-period from beginning until the electrode impedancecan be fixed.

Once the wearable is properly situated and secured onto the subject'shead, and the impedance of each of the electrodes is at an acceptablelevel, the step of providing a low dose direct electrical current fromthe at least one surface scalp electrode for providing a low dose directelectrical current across the subject's cranium to stimulate at leastone area of the subject's brain at a pre-determined duty-cycle, the areaof the subject's brain being stimulated corresponding to at least onesymptom of a movement disorder to reduce the occurrence, severity,and/or duration of movement disorder symptoms, can begin. In this step,a current generator begins to supply a direct current at a known, steadyamperage, through at least one electrode, across the subject's cranium,and into the brain. This current is preferably targeted at a particulararea of the subject's brain which corresponds to the occurrence ofmovement disorder symptoms. For example, using the direct electricalcurrent to stimulate the basal ganglia may have a positive effect inreducing bradykinesia. The method by which the current is applieddepends largely on the type of electrodes used. Traditional tDCS systemsused in laboratory settings typically use a large (e.g. 25-35 cm²)saline-soaked sponge electrodes which are not practical for home use.Another option is to use a still relatively large (e.g., 5×7 cm)electrode pad; however, these large electrode pads may increase scalptemperature causing discomfort to the subject, and typically result incurrent being concentrated around the edges of the electrode pad, andthus less accurately delivered to a targeted brain area.

All embodiments of the present invention will utilize electrodes. Theelectrodes used may be any of those commonly known in the art of tDCSand EEG monitoring. The electrodes preferably do not require theapplication of conductive paste or gel. Therefore, the electrode lead orarray preferably has any necessary conductive fluids pre-applied. Evenmore preferably, the electrodes are dry physiological electrodesrequiring no conductive fluid at all. Dry physiological recordingelectrodes of the type described in U.S. Pat. No. 6,785,569 can be used.U.S. Pat. No. 6,785,569 is hereby incorporated by reference. Dryelectrodes provide the advantage that there is no gel to dry out, noskin to abrade or clean, and that the electrode can be applied in hairy,sweaty, and/or dirty areas such as the scalp, particularly forin-the-field applications. The electrode lead or array may be affixed toor embedded into a flexible, wearable apparatus which can be applieddirectly to the subject's head at the desired location, as discussedabove.

In some embodiments, least two surface scalp electrodes affixed to orembedded in the wearable, at least one electrode for providing a lowdose direct electrical current to the subject, and at least oneelectrode for return of the low dose direct electrical current, areprovided. Typically for tDCS, such electrodes are placed on oppositesides of the subject's head. As such, one electrode is used to providethe current directly across the subject's cranium, through the brain,and is drawn out the other side through the return electrode. However,the present invention may utilize a two electrode configuration whereinthe two electrodes are applied near each other, on the same side of thesubject's head, thus supplying the current to the desired brain locationand drawing it out the same side. Preferably, the anodal electrode ispositioned in such a manner so as to deliver the therapeutic current tothe patient's primary motor cortex (C3 or C4) contralateral to the moreeffected side.

Some embodiments may employ a dual stimulation approach wherein bothanodal and cathodal stimulation are provided simultaneously. Anodalstimulation increases the excitability of the targeted region whereascathodal stimulation tends to decrease such excitability. In suchembodiments, the anodal stimulation is still provided to the region ofthe subject's brain that corresponds to the particular symptom(s) whichare being targeted. Cathodal stimulation, however, is supplied to theunaffected portion of the brain that is the counterpart to the affectedregion, or corresponds to the other side of the subject which is notsymptomatic. In other words, anodal stimulation increases theexcitability of the portion of the brain giving rise to the movementdisorder symptoms, and cathodal stimulation decreases the excitabilityof the counterpart regions which do not correspond to symptoms. Intypical tDCS therapy, there is always an anode and a cathode, thoughtypically the cathode is placed in an area where it provides nostimulation to the brain, but merely serves to draw the electricalcurrent out along a safe path. In embodiments using the dual stimulationmethod, the cathode is placed in a location so as to provide stimulationto the subject's brain as described above. Such dual stimulation may beperformed simultaneously, according to the same duty cycle. In suchembodiments, the affected and unaffected sides would receive anodal andcathodal stimulation, respectively, at the same time, and suchstimulation would be turned on and off at the same time according to thesame duty cycle.

In other, more preferred embodiments, an array of at least five surfacescalp electrodes is supplied. In such embodiments, all at least fiveelectrodes are applied on the same side of the subject's head. The atleast five electrodes may be individual, or may be affixed to orembedded into a patch or similar apparatus for keeping the electrodes ina stable arrangement with respect to each other. In many embodiments,the electrodes may preferably each be individually addressable, and ableto be be removed and replaced individually without affecting the otherelectrodes in the array. In light of the description of a wearableapparatus above, it is preferably possible to remove and/or insert anindividual electrode into the wearable. Some embodiments may utilize acombination of these features wherein the electrodes are affixed to orembedded individually into a patch-like apparatus, and wherein saidpatch is then inserted into the wearable which is applied to thesubject's head, thus maintaining individual addressability of theelectrodes and making it easier to replace the electrode array on aperiodic basis.

In a preferred embodiment, the electrodes provided are small electrodesprovided in an array. Preferably, in such embodiments, the electrodesare arranged in a 4×1 ring array. By this, it is meant that there is atleast one central anodal electrode surrounded by at least four returnelectrodes arranged in a ring around the anodal electrode. The centralanodal electrode is used to supply the direct current to the subject'sbrain, and the four return electrodes arranged around the central anodalelectrode are used to draw the current back out of the brain. Sucharrangement is preferred because it has been shown to not significantlyraise scalp temperature, nor to modulate cortex in undesired regions.This helps to minimize the subject's discomfort and to more efficientlyeffect the desired therapy on the subject. Preferably, the smallelectrodes are as described above: either pre-applied with gel, or morepreferably, dry electrodes requiring no conductive gels or pastes atall. By small, it is meant that the electrodes are preferably less than3 cm in diameter. More preferably, the electrodes are less than 2.5 cmin diameter. Even more preferably, the electrodes are less than 2 cm indiameter. Still more preferably, the electrodes are less than 1.5 indiameter. Yet more preferably, the electrodes are less than 1 cm indiameter. Still yet more preferably, the electrodes are less than 8 mmin diameter. Even still more preferably the electrodes are less than 5mm in diameter. Another way to describe the electrode size for use withthe present invention is in regards to surface area. Preferably, theelectrodes have a surface area that is less than 8 cm². More preferably,the electrodes have a surface area that is less than 5 cm². Yet morepreferably, the electrodes have a surface area that is less than 4 cm².Still more preferably, the electrodes have a surface area that is lessthan 2 cm². Even more preferably, the electrodes have a surface areathat is less than 1 cm². Still yet more preferably, the electrodes havea surface area that is less than 75 mm². Even yet more preferably, theelectrodes have a surface area that is less than 50 mm². Even still morepreferably, the electrodes have a surface area that is less than 25 mm².

Another element of all embodiments of the present invention is aprocessor comprising a stimulation control program for controlling howthe low dose electrical current is provided to the subject. Theprocessor can be any type of computer or controller suitable to compriseand run a control program for the current generator. Preferably theprocess is small in that it does not take up large amount of space, andcan be easily stored, and kept relatively inconspicuously near thesubject while he or she sleeps. Preferably, the processor is amicro-processor that can be integrated into other hardware thisminimizing the size of the device. Further preferably, the entire deviceis miniaturized and thus portable, so the subject is able to easilytransport the device for use while travelling or otherwise away fromhome.

The stimulation control program is the program that controls the desiredduty cycle for the therapeutic electrical current. The control programmay be tailored and custom-programmed for each subject based on his orher particular movement disorder, symptoms, and other physiological orother concerns. The stimulation control program may further determinewhen to initiate the on-period of the duty cycle based on real-timesubject specific parameters. For example, the duty cycle may becontrolled based at least on part on the subject's sleep stage. In suchembodiments, the system may detect the patient's sleep stage and thendetermine when to initiate therapy. Typically, sleep stages areseparated into two major categories: rapid eye movement (REM), andnon-REM sleep. The non-REM stage is further subdivided into as many asfour separate categories: Stage 1, characterized by theta activity ofhigh amplitude, slow moving brain waves (typically between 3.5-7.5 Hz)which is between wakefulness and sleep; Stage 2, characterized by thebeginning of rapid, rhythmic brain activity known as sleep spindles;Stage 3, characterized by the onset of delta activity of deep, slowbrain waves; and Stage 4, characterized by further, sustained delta waveactivity. REM activity, or deep sleep characterized by increased brainactivity and rapid eye movement, is the fifth stage and follows Stage 4.With regard to the stimulation control program, the system may initiatetherapy when the patient any of these stages of sleep, though preferablyat least waits until stage 2 at which point the patient is actuallyconsidered to be asleep. In such embodiments, the duty cycle may then becontrolled on a strict time period basis where the current is on for apredetermined amount of time, and then off for a separate predeterminedtime period. Alternatively, once therapy is initiated in suchembodiments, the duty cycle may be controlled based on changes in thesleep cycle, that is, the current may be provided during a period ofsleep, and turned off when the patient transitions to a new phase, oraccording to combinations of phases.

Alternatively, the duty cycle may be controlled solely on a time basis,that is, initiated a given amount of time after the onset of sleep, andcycled at a predetermined interval thereafter until the subject awakens.Preferably, the duty cycle of the therapeutic current delivery is ongreater than 5% of the time. More preferably, the duty cycle of thetherapeutic current delivery is on greater than 10% of the time. Stillmore preferably, the duty cycle of the therapeutic current delivery ison greater than 15% of the time. Even more preferably, the duty cycle ofthe therapeutic current delivery is on greater than 20% of the time. Yetmore preferably, the duty cycle of the therapeutic current delivery ison greater than 25% of the time. Still yet more preferably, the dutycycle of the therapeutic current delivery is on greater than 30% of thetime. Even yet more preferably, the duty cycle of the therapeuticcurrent delivery is on greater than 35% of the time. Even still morepreferably, the duty cycle of the therapeutic current delivery is ongreater than 40% of the time. Even still yet more preferably, the dutycycle of the therapeutic current delivery is on greater than 45% of thetime.

Another way to characterize the provision of the therapeutic current tothe subject is in terms of the total time of each “on” cycle.Preferably, the current is provided for at least 10 minutescontinuously. More preferably, the current is provided for at least 20minutes continuously. Still more preferably, the current is provided forat least 30 minutes continuously. Even more preferably, the current isprovided for at least 40 minutes continuously. Yet more preferably, thecurrent is provided for at least 45 minutes continuously. Still yet morepreferably, the current is provided for at least 50 minutescontinuously. Even still more preferably, the current is provided for atleast 60 minutes continuously.

With regard to the “off” cycle, preferably the current is off for atleast 10 minutes before being turned on again. More preferably, thecurrent is off for at least 20 minutes before being turned on again.Still more preferably, the current is off for at least 30 minutes beforebeing turned on again. Yet more preferably, the current is off for atleast 45 minutes before being turned on again. Even still morepreferably, the current is off for at about 60 minutes before beingturned on again.

Another component of many embodiments of the present invention is acurrent generator for providing a low-dose (low current) electricalstimulation impulse through the at least one electrode for providing alow dose direct electrical current to the subject. The current generatoris preferably able to provide a sustained direct current with little tono variability in amperage. By sustained, it is meant that preferablythe current generator is capable of providing the current according tothe varying requirements of the control program as described above.Additionally, the current generator is preferably capable of providingan alternating current at a known frequency and amplitude in order tomeasure electrical impedance of the electrodes as described above.Alternatively, a second current generator may be provided, thus havingone generator for providing the therapeutic direct current, and a secondgenerator for providing an alternating current for electrode impedancemeasurement.

Now referring to FIGS. 1-9, FIG. 1 portrays a subject 100, lying sleep,wearing one embodiment of the device 102 and 104. In this figure, thesubject 100, or another person, has placed the device 102 and 104 uponhis head and he is now asleep. The particular embodiment of the devicedepicted in this figure comprises a head band 102 enclosure thatencompasses the subject's 100 head and holds the electrode array 104securely in place contacting the subject's 100 skin. The individualelectrodes are affixed to, embedded in, or otherwise integrated into apad that is easily attached to the subject and remains securely in placethrough the subject's sleep time 108. The electrode array 104 in thisembodiment is shown to be a 4×1 array with one central anodal electrodefor delivering the therapeutic tDCS current (not shown) to the subject'sbrain, and four (only three visible) return electrodes to draw thecurrent back out of the subject's brain. As described, the head band canbe secured about the subject's 100 head by any means commonly known tothose of skill in the art, or later developed.

Once the subject 100 dons the device 102 and 104 and falls asleep, thetDCS therapy (not shown) can be applied according to several parameterswhile the subject 100 is asleep 110. The system is not designed toreplace medication, but rather to supplement its use. Normally, when asubject or patient goes to sleep, the medication wears off over time,and the subject or patient awakens with noticeably worse symptoms due tothe low or non-existent concentration of drugs in his or her system.However, the application of a therapeutic tDCS current to the subject'sbrain while he or she sleeps helps to counteract the fall-off of themedication in the subject's blood stream and minimize the resultingincrease in symptom occurrence and severity 112, and may even helpdecrease the amount of medication needed while awake 106.

FIG. 2 portrays a particular embodiment of the present invention whereinthe device is a custom-molded cap-style wearable apparatus 150. In suchembodiments, the cap is custom molded to fit each particular subject'shead. The electrodes, or electrode array, are again affixed to, embeddedin, or otherwise integrated into the wearable cap 150. In thisparticular embodiment, the electrodes 152 and 154 are again arrangedinto a 4×1 electrode array comprising a central anodal electrode 154 fordelivering the therapeutic tDCS current, and four return electrodes 152for drawing the current back out. The electrodes 152 and 154 orelectrode array can be fitted, attached, or integrated directly into thematerial of the wearable cap 150, or can be so attached to a patch whichis then affixed to, embedded in, or otherwise attached to the wearablecap. In all embodiments, the electrodes 152 and 154 or the electrodearray are preferably easily removed, individually, to be replaced. Anindividual electrode may be replaced, or the entire array may bereplaced, as necessary, but no matter the arrangement, removal andinsertion of new electrodes is easy and requires no formal training.Furthermore, the custom-fitted cap 150 provides the best model forrepeated, sustainable placement of the electrodes in the desiredlocation, with minimum opportunity for incorrect donning and improperplacement of the electrodes. Each time the subject dons the cap 150, theelectrodes will be located in the exact same desired location.

FIG. 3 depicts a flow chart of one embodiment of a method of the presentinvention. First, a wearable comprising at least two surface scalpelectrodes is provided 250. The wearable can be of any variety describedabove, including, but not limited to, a custom fit cap, a belt or band,an adjustable cap, or any other variety of wearable which can be worncomfortably yet securely and in a stable manner about the subject'shead. Of the at least two electrodes, one is for providing a therapeutictDCS current across the subject's scalp and cranium and into his or herbrain, and the at least one other electrode is used to draw the currentback out of the subject. The electrodes are preferably dry surface scalpelectrodes which require little or no preparation of the skin, little orno electrolytic or other conductive fluids or gels, and no implantationinto the subject. The electrodes are merely affixed to, embedded in, orotherwise attached to the wearable.

Next, the wearable comprising the at least two electrodes is placed onthe subject's head to be worn while the subject is asleep 252. Themethod of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the subject is asleep, a low dose electrical current isapplied from one of the at least two electrodes, across the subject'sscalp and cranium 254. The current is applied according to apredetermined duty cycle as described above, and the electrodes areplaced in such a manner as to apply the current to target a particularportion of the subject's brain that corresponds to at least one symptomof a movement disorder. Applying the tDCS current in this manner thusreduces the occurrence, severity, and or duration of movement disordersymptom activity for the subject. In the particular embodiment depictedin this figure, the tDCS current is applied in a manner so as tominimize cortex modulation in the frontal region, contralateral region,and occipital lobe of the subject's brain. The tDCS therapy continuesaccording to the predetermined duty cycle until the patient awakes. Ifthe system detects that the therapy session is complete (e.g. patientawakens, predetermined time period of therapy has lapsed, predeterminednumber of therapeutic cycles have completed, sleep stage as changed,etc.) 256, the therapy session stops 258, and no further current isapplied. However, if the therapy session is not complete (i.e., thepatient is still asleep, predetermined number of therapeutic cycles hasnot completed, sleep stage indicates therapy should continue, etc.) thetherapy continues, that is the duty cycle off period begins (the currentis temporarily turned off) 260, until the system detects or determinesthat the duty cycle on period should begin again, and the current isturned on 254. This process is then repeated until the therapy sessionis completed.

FIG. 4 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is provided 300. The wearable canbe of any variety described above, including, but not limited to, acustom fit cap, a belt or band, an adjustable cap, or any other varietyof wearable which can be worn comfortably yet securely and in a stablemanner about the subject's head. Further, an array of at least fiveelectrodes is provided 302. The electrodes are preferably dry surfacescalp electrodes which require little or no preparation of the skin,little or no electrolytic or other conductive fluids or gels, and noimplantation into the subject. Preferably, the at least five electrodesare arranged in at least a 4×1 ring. There should be a single, centralanodal electrode that is used to provide the therapeutic tDCS current tothe subject's brain. The at least four, and any additional otherelectrodes, should be arranged around the central, anodal electrode in aring structure. These outer electrodes are then utilized to draw thetDCS current back out of the subject. The electrodes are then affixedto, embedded in, or otherwise attached to the wearable as previouslydescribed 304.

Next, the wearable comprising the array of at least five electrodes isplaced on the subject's head to be worn while the subject is asleep 306.The method of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the subject is asleep, a low dose electrical current isapplied from one of the at least two electrodes, across the subject'sscalp and cranium 308. In this particular embodiment, therapy isprovided in constant current mode, with the low dose electrical currentbeing provided at about 2 mA. The current is applied according to apredetermined duty cycle as described above, and the electrodes areplaced in such a manner as to apply the current to target a particularportion of the subject's brain that corresponds to at least one symptomof a movement disorder. Applying the tDCS current in this manner thusreduces the occurrence, severity, and or duration of movement disordersymptom activity for the subject. Additionally, another embodiment of asimilar method further includes a predetermined duty cycle of 33% (notshown), wherein the tDCS current is on for about 33% of each cycle andoff for about 66% of each cycle. In such alternative embodiment, anexemplary cycle period would be 3 hours, where the tDCS current is onfor one hour, off for two hours, and then repeated. In either embodiment(comprising the specific 33% duty cycle or some other duty cycle), thetDCS therapy continues according to the predetermined duty cycle untilthe system determines that the therapy session is complete. If thesystem detects that the therapy session is complete (e.g. patientawakens, predetermined time period of therapy has lapsed, predeterminednumber of therapeutic cycles have completed, etc.) 256, the therapysession stops 258, and no further current is applied. However, if thetherapy session is not complete (i.e., the patient is still asleep,predetermined number of therapeutic cycles has not completed, sleepstage indicates therapy should continue, etc.) the therapy continues,that is the duty cycle off period begins (the current is temporarilyturned off) 260, until the system detects or determines that the dutycycle on period should begin again, and the current is turned on 308.This process is then repeated until the therapy session is completed.

FIG. 5 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is provided 300. The wearable canbe of any variety described above, including, but not limited to, acustom fit cap, a belt or band, an adjustable cap, or any other varietyof wearable which can be worn comfortably yet securely and in a stablemanner about the subject's head. Next, an array of at least 5 surfacescalp electrodes is affixed to, embedded in, or otherwise attached tothe wearable as previously described 350. The electrodes are preferablydry surface scalp electrodes which require little or no preparation ofthe skin, little or no electrolytic or other conductive fluids or gels,and no implantation into the subject. Preferably, the at least fiveelectrodes are arranged in at least a 4×1 ring. There should be asingle, central anodal electrode that is used to provide the therapeutictDCS current to the subject's brain. The at least four, and anyadditional other electrodes, should be arranged around the central,anodal electrode in a ring structure. These outer electrodes are thenutilized to draw the tDCS current back out of the subject.

Next, the wearable comprising the array of at least five electrodes isplaced on the subject's head to be worn while the subject is asleep 352.The method of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the subject is asleep, a low dose electrical current isapplied from one of the at least two electrodes, across the subject'sscalp and cranium 354. The current is applied according to apredetermined duty cycle as described above, and the electrodes areplaced in such a manner as to apply the current to target a particularportion of the subject's brain that corresponds to at least one symptomof a movement disorder. Applying the tDCS current in this manner thusreduces the occurrence, severity, and or duration of movement disordersymptom activity for the subject. In the particular embodiment depictedin this figure, the tDCS current is applied at substantially 2 mA(milli-amps), and the duty cycle is about 33%. The tDCS therapycontinues according to the predetermined duty cycle until the patientawakes. If the system detects that the therapy session is complete (e.g.patient awakens, predetermined time period of therapy has lapsed,predetermined number of therapeutic cycles have completed, etc.) 256,the therapy session stops 258, and no further current is applied.However, if the therapy session is not complete (i.e., the patient isstill asleep, predetermined number of therapeutic cycles has notcompleted, sleep stage indicates therapy should continue, etc.) thetherapy continues, that is the duty cycle off period begins (the currentis temporarily turned off) 260, until the system detects or determinesthat the duty cycle on period should begin again, and the current isturned on 354. This process is then repeated until the therapy sessionis completed.

FIG. 6 is a flow chart of another embodiment of a method of the presentinvention. First, a flexible apparatus and an electrode array areprovided and placed upon a subject's head 400. In this particularembodiment, the wearable is some variety of a flexible harness. Further,in this particular embodiment, the electrode array is not affixed to orembedded into the harness, but rather the array and the harness areseparate, individual pieces, and the flexible harness is used to holdthe array in place once placed on the subject's head. As above, theharness may be secured above the subject's head in any manner commonlyknown to those of skill in the art. Further, the electrodes of theelectrode array are preferably dry surface scalp electrodes whichrequire little or no preparation of the skin, little or no electrolyticor other conductive fluids or gels, and no implantation into thesubject. Preferably, the at least five electrodes are arranged in atleast a 4×1 ring. There should be a single, central anodal electrodethat is used to provide the therapeutic tDCS current to the subject'sbrain. The at least four, and any additional other electrodes, should bearranged around the central, anodal electrode in a ring structure. Theseouter electrodes are then utilized to draw the tDCS current back out ofthe subject. The array may, and preferably, is additionally secured tothe subject's head by means of an adhesive layer which adheres the arrayto the subject's scalp. The flexible harness then provides additionalstability and security to the placement of the electrode array.

Once the array and harness are placed onto the subject's head, a lowdose electrical current is applied from one of the at least twoelectrodes, across the subject's scalp and cranium 402. The current isapplied according to a predetermined duty cycle as described above, andthe electrodes are placed in such a manner as to apply the current totarget a particular portion of the subject's brain that corresponds toat least one symptom of a movement disorder. In this particularembodiment, the tDCS current is applied substantially at 2 mA and theon-time for the current is at least 30 minutes. Thus, for example, ifthe duty cycle is 33%, where the current is on for thirty minutes, the33% duty cycle then dictates that the current would be off for one hourbefore reinitiating the on-cycle. However, the current may be on forlonger than 30 minutes, and the duty cycle may be other than 33%, or maybe dynamically adjusted based on the subject's needs substantially inreal time, in which case the off-period would adjust accordingly tomaintain the appropriate duty cycle. The tDCS therapy continuesaccording to the duty cycle until the patient awakes. If the systemdetects that the therapy session is complete (e.g. patient awakens,predetermined time period of therapy has lapsed, predetermined number oftherapeutic cycles have completed, etc.) 256, the therapy session stops258, and no further current is applied. However, if the therapy sessionis not complete (i.e., the patient is still asleep, predetermined numberof therapeutic cycles has not completed, sleep stage indicates therapyshould continue, etc.) the therapy continues, that is the duty cycle offperiod begins (the current is temporarily turned off) 260, until thesystem detects or determines that the duty cycle on period should beginagain, and the current is turned on 402. This process is then repeateduntil the therapy session is completed.

FIG. 7 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is provided 300. The wearable canbe of any variety described above, including, but not limited to, acustom fit cap, a belt or band, an adjustable cap, or any other varietyof wearable which can be worn comfortably yet securely and in a stablemanner about the subject's head. Further, an array of at least fiveelectrodes is provided 450. The electrodes are preferably dry surfacescalp electrodes which require little or no preparation of the skin,little or no electrolytic or other conductive fluids or gels, and noimplantation into the subject. Preferably, the at least five electrodesare arranged in at least a 4×1 ring. There should be a single, centralanodal electrode that is used to provide the therapeutic tDCS current tothe subject's brain. The at least four, and any additional otherelectrodes, should be arranged around the central, anodal electrode in aring structure. These outer electrodes are then utilized to draw thetDCS current back out of the subject. The electrodes are then affixedto, embedded in, or otherwise attached to the wearable as previouslydescribed 452.

Next, the wearable comprising the array of at least five electrodes isplaced on the subject's head to be worn while the subject is asleep 454.The method of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the wearable is placed on the subject's head (regardless ofwhether subject is asleep), the system may then check the electricalimpedance of each of the electrodes 456. The impedance check can beperformed according to any of the methods disclosed above. However,before the therapeutic tDCS current is applied, the electrical impedanceof each electrode must be checked and verified to be low enough in orderfor the therapy cycle to begin. In the event that an electrode'simpedance is too high, the system will notify the subject or user toreplace that electrode. Only then will the therapy session be able tobegin.

Once the electrodes are all verified to be in proper working condition,the current is applied according to a predetermined duty cycle asdescribed above, and the electrodes are placed in such a manner as toapply the current to target a particular portion of the subject's brainthat corresponds to at least one symptom of a movement disorder 458.Applying the tDCS current in this manner thus reduces the occurrence,severity, and or duration of movement disorder symptom activity for thesubject. In the particular embodiment depicted in this figure, the tDCScurrent is applied at substantially 2 mA (milli-amps). The tDCS therapycontinues according to the predetermined duty cycle until the patientawakes. If the system detects that the therapy session is complete (e.g.patient awakens, predetermined time period of therapy has lapsed,predetermined number of therapeutic cycles have completed, etc.) 256,the therapy session stops 258, and no further current is applied.However, if the therapy session is not complete (i.e., the patient isstill asleep, predetermined number of therapeutic cycles has notcompleted, sleep stage indicates therapy should continue, etc.) thetherapy continues, that is the duty cycle off period begins (the currentis temporarily turned off) 260, until the system detects or determinesthat the duty cycle on period should begin again, and the current isturned on 458. This process is then repeated until the therapy sessionis completed.

FIG. 8 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is provided 300. The wearable canbe of any variety described above, including, but not limited to, acustom fit cap, a belt or band, an adjustable cap, or any other varietyof wearable which can be worn comfortably yet securely and in a stablemanner about the subject's head. Further, at least two electrodes areprovided 500, one of which is for providing a therapeutic tDCS currentacross the subject's scalp and cranium and into his or her brain, andthe at least one other electrode is used to draw the current back out ofthe subject. The electrodes are preferably dry surface scalp electrodeswhich require little or no preparation of the skin, little or noelectrolytic or other conductive fluids or gels, and no implantationinto the subject. The electrodes are then affixed to, embedded in, orotherwise attached to the wearable as previously described 502.

Next, the wearable comprising the at least two electrodes is placed onthe subject's head to be worn while the subject is asleep 504. Themethod of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the wearable is placed on the subject's head (regardless ofwhether subject is asleep), the system may then check the electricalimpedance of each of the electrodes 506. The impedance check can beperformed according to any of the methods disclosed above. However,before the therapeutic tDCS current is applied, the electrical impedanceof each electrode must be checked and verified to be low enough in orderfor the therapy cycle to begin. In the event that an electrode'simpedance is too high, the system will notify the subject or user toreplace that electrode. Only then will the therapy session be able tobegin.

Once the electrodes are all verified to be in proper working condition,the current is applied according to a predetermined duty cycle asdescribed above, and the electrodes are placed in such a manner as toapply the current to target a particular portion of the subject's brainthat corresponds to at least one symptom of a movement disorder 508.Applying the tDCS current in this manner thus reduces the occurrence,severity, and or duration of movement disorder symptom activity for thesubject. In the particular embodiment depicted in this figure, the tDCScurrent is applied at substantially 2 mA (milli-amps). The tDCS therapycontinues according to the predetermined duty cycle until the patientawakes. If the system detects that the therapy session is complete (e.g.patient awakens, predetermined time period of therapy has lapsed,predetermined number of therapeutic cycles have completed, etc.) 256,the therapy session stops 258, and no further current is applied.However, if the therapy session is not complete (i.e., the patient isstill asleep, predetermined number of therapeutic cycles has notcompleted, sleep stage indicates therapy should continue, etc.) thetherapy continues, that is the duty cycle off period begins (the currentis temporarily turned off) 260, until the system detects or determinesthat the duty cycle on period should begin again, and the current isturned on 508. This process is then repeated until the therapy sessionis completed.

FIG. 9 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is custom fitted to fit asubject's head 500. The wearable can be made of any material and/ormethod commonly known to those in the art, and should be able to be worncomfortably yet securely and in a stable manner about the subject'shead. In order to custom fit the wearable to a particular subject, thesubject will likely need to be present for a consultation in whichmeasurements are taken, a mold is made, or some other precise modelingmethod is used. The modeling method may be any of those currently knownto those of skill in the art, or any method later developed. Themeasurement, mold, or model can then be used to create a custom-fitwearable that conforms to the particular shape, size, and contours ofthe subject's head. This method further helps to provide precise,repeatable placement of the electrodes each time the subject dons thewearable.

Further, an array of at least five electrodes is provided 552. Theelectrodes are preferably dry surface scalp electrodes which requirelittle or no preparation of the skin, little or no electrolytic or otherconductive fluids or gels, and no implantation into the subject.Preferably, the at least five electrodes are arranged in at least a 4×1ring. There should be a single, central anodal electrode that is used toprovide the therapeutic tDCS current to the subject's brain. The atleast four, and any additional other electrodes, should be arrangedaround the central, anodal electrode in a ring structure. These outerelectrodes are then utilized to draw the tDCS current back out of thesubject. The electrodes are then affixed to, embedded in, or otherwiseattached to the wearable as previously described 554.

Next, the wearable comprising the array of at least five electrodes isplaced on the subject's head to be worn while the subject is asleep 556.The method of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the wearable is placed on the subject's head (regardless ofwhether subject is asleep), the system may then check the electricalimpedance of each of the electrodes 558. The impedance check can beperformed according to any of the methods disclosed above. However,before the therapeutic tDCS current is applied, the electrical impedanceof each electrode must be checked and verified to be low enough in orderfor the therapy cycle to begin. In the event that an electrode'simpedance is too high, the system will notify the subject or user toreplace that electrode. Only then will the therapy session be able tobegin.

Once the electrodes are all verified to be in proper working condition,the current is applied according to a predetermined duty cycle asdescribed above, and the electrodes are placed in such a manner as toapply the current to target a particular portion of the subject's brainthat corresponds to at least one symptom of a movement disorder 560.Applying the tDCS current in this manner thus reduces the occurrence,severity, and or duration of movement disorder symptom activity for thesubject. The tDCS therapy continues according to the predetermined dutycycle until the patient awakes. If the system detects that the therapysession is complete (e.g. patient awakens, predetermined time period oftherapy has lapsed, predetermined number of therapeutic cycles havecompleted, etc.) 256, the therapy session stops 258, and no furthercurrent is applied. However, if the therapy session is not complete(i.e., the patient is still asleep, predetermined number of therapeuticcycles has not completed, sleep stage indicates therapy should continue,etc.) the therapy continues, that is the duty cycle off period begins(the current is temporarily turned off) 260, until the system detects ordetermines that the duty cycle on period should begin again, and thecurrent is turned on 560. This process is then repeated until thetherapy session is completed.

FIG. 10 is a flow chart of another embodiment of a method of the presentinvention. First, a wearable apparatus is provided 600. The wearable canbe of any variety described above, including, but not limited to, acustom fit cap, a belt or band, an adjustable cap, or any other varietyof wearable which can be worn comfortably yet securely and in a stablemanner about the subject's head. Further, an array of at least fiveelectrodes is provided 602. The electrodes are preferably dry surfacescalp electrodes which require little or no preparation of the skin,little or no electrolytic or other conductive fluids or gels, and noimplantation into the subject. Preferably, the at least five electrodesare arranged in at least a 4×1 ring. There should be a single, centralanodal electrode that is used to provide the therapeutic tDCS current tothe subject's brain. The at least four, and any additional otherelectrodes, should be arranged around the central, anodal electrode in aring structure. These outer electrodes are then utilized to draw thetDCS current back out of the subject. The electrodes are then affixedto, embedded in, or otherwise attached to the wearable as previouslydescribed 604.

Next, the wearable comprising the array of at least five electrodes isplaced on the subject's head to be worn while the subject is asleep 606.The method of donning the wearable depends on the particular form thewearable takes. Regardless of said form, the wearable apparatus isplaced on the subject's head, and he or she then settles in to go tosleep. Once the apparatus with electrode array is placed on thesubject's head and the subject falls asleep, the system then begins tomonitor the subject's sleep stage 608. The system may use any meanscurrently known to those in the art, or later developed, in order todetermine the sleep stage in which the subject is sleeping. By way ofnon-limiting example, an EEG signal may be used to determine thesubject's sleep stage. This sleep stage determination is preferably madesubstantially in real-time, and the system then turns on thetherapeutic, thus beginning the duty cycle, of the tDCS therapy. Theparticular sleep stage which triggers the beginning of the therapy cyclemay be different for individual subjects, symptoms being treated, or anyother variable. The therapeutic current is applied according to apredetermined duty cycle, and based at least in part on the detectedsleep stage of the subject, as described above, and the electrodes areplaced in such a manner as to apply the current to target a particularportion of the subject's brain that corresponds to at least one symptomof a movement disorder 610. Further, the stimulation applied may bechanged throughout a given therapy session based on factors such assleep stage, or the like. Applying the tDCS current in this manner thusreduces the occurrence, severity, and or duration of movement disordersymptom activity for the subject. The tDCS therapy continues accordingto the predetermined duty cycle until the patient awakes. If the systemdetects that the therapy session is complete because the subject hasentered a different sleep stage that does not correspond to the desiredtreatment, or the therapy session otherwise is determined to be complete(e.g. patient awakens, predetermined time period of therapy has lapsed,predetermined number of therapeutic cycles have completed, etc.) 612,the therapy session stops 258, and no further current is applied. In thedepicted embodiment, the main determinant is the subject's sleep stage.If, for example, the therapy is predetermined to only occur (i.e., tDCScurrent supplied) while the subject is in REM sleep, then when thesystem determines that the subject leaves REM sleep, the systemdetermines 616 to shut off the current and stop therapy 258. Conversely,if the system determines that the subject is still in the desired stageof sleep but the duty cycle or predetermined time period for currenton-time has completed, the system determines 614 that the current shouldbe temporarily shut off, and that the duty cycle should control 260 whenthe therapeutic current is again turned on 610. This process is thenrepeated until the therapy session is completed.

While a preferred embodiment is disclosed herein, it will be apparent tothose skilled in the art that various modifications and variations canbe made to the present invention without departing from the spirit andscope of the invention. Thus, it is intended that the present inventioncover the modifications and variations of this invention provided theycome within the scope of the appended claims and their equivalents.

The invention claimed is:
 1. A transcranial direct current stimulation (tDCS) system for providing treatment or therapy for movement disorders or memory of a subject, the system comprising: at least two surface scalp electrodes, at least one anodal electrode, and at least one cathodal electrode, the at least two surface scalp electrodes adapted to be worn by or attached to the subject during sleep, and adapted to be positioned such that at least one low-dose anodal direct electrical current provided from the at least one anodal electrode is directed to stimulate at least one desired location or area of the subject's brain; and a current generation device adapted to provide the at least one low dose anodal direct electrical current from the anodal electrode to stimulate the at least one desired location or area of the subject's brain at a pre-determined duty-cycle, wherein electrodes are adapted to be positioned such that the desired at least one location or area of the subject's brain stimulated by the low dose anodal direct electrical current corresponds to at least one symptom of a movement disorder or memory.
 2. The system of claim 1, wherein the at least 2 electrodes are affixed to or embedded in a wearable apparatus.
 3. The system of claim 1, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected theta brain wave activity.
 4. The system of claim 1, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected delta brain wave activity.
 5. The system of claim 1, wherein and the current generation device is further adapted to provide at least one cathodal stimulation current from the at least one cathodal electrode substantially simultaneously with the provided anodal stimulation current.
 6. The system of claim 1, wherein the current generation device is adapted to turn on the duty cycle greater than 33% of the time during sleep stage(s) corresponding to slow brain waves.
 7. The system of claim 1, wherein the system is adapted to check impedance of the at least two electrodes when the duty-cycle is off.
 8. A transcranial direct current stimulation (tDCS) system for providing treatment or therapy for movement disorders or memory of a subject, the system comprising: at least two surface scalp electrodes, at least one electrode for providing at least one low dose direct electrical current to the subject, and at least one electrode for return of the at least one low dose direct electrical current, the at least two surface scalp electrodes adapted to be worn by or attached to the subject during sleep, and adapted to be positioned such that at least one low-dose direct electrical current provided is directed to stimulate at least one desired location or area of the subject's brain; a current generation device adapted to provide the at least one low dose direct electrical current from the at least one surface scalp electrode for providing a low dose direct electrical current across the subject's cranium to stimulate the at least one desired location or area of the subject's brain at a pre-determined duty-cycle during at least one stage of sleep corresponding to slow brain waves, wherein electrodes are adapted to be positioned such that the desired at least one location or area of the subject's brain stimulated by the low dose anodal direct electrical current corresponds to at least one symptom of a movement disorder or memory.
 9. The system of claim 8, wherein the at least 2 electrodes are affixed to or embedded in a wearable apparatus.
 10. The system of claim 9, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected theta brain wave activity.
 11. The system of claim 8, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected delta brain wave activity.
 12. The system of claim 11, wherein the current generation device is adapted to turn on the duty cycle greater than 33% of the time during sleep stage(s) corresponding to slow brain waves.
 13. The system of claim 8, wherein the current generation device is adapted to turn off the duty cycle corresponding to a detected sleep stage corresponding to fast or rapid brain waves.
 14. The system of claim 8, wherein the system is adapted to check impedance of the at least two electrodes when the duty-cycle is off.
 15. A transcranial direct current stimulation (tDCS) system for providing treatment or therapy for movement disorders or memory of a subject, the system comprising: a wearable apparatus comprising an embedded or affixed electrode array, the electrode array comprising at least two surface scalp electrodes, at least one electrode for providing at least one low dose direct electrical current to the subject, and at least one electrode for return of the at least one low dose direct electrical current, the at least two surface scalp electrodes adapted to be worn by or attached to the subject during sleep, and adapted to be positioned such that at least one low-dose direct electrical current provided is directed to stimulate at least one desired location or area of the subject's brain; a current generation device adapted to provide the at least one low dose direct electrical current from the at least one surface scalp electrode for providing a low dose direct electrical current across the subject's cranium to stimulate the at least one desired location or area of the subject's brain at a predetermined duty-cycle during at least one stage of sleep corresponding to slow brain waves, wherein electrodes are adapted to be positioned such that the desired at least one location or area of the subject's brain stimulated by the low dose anodal direct electrical current corresponds to at least one symptom of a movement disorder or memory.
 16. The system of claim 15, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected theta brain wave activity.
 17. The system of claim 15, wherein the current generation device is adapted to turn on the duty cycle corresponding to detected delta brain wave activity.
 18. The system of claim 17, wherein the current generation device is adapted to turn on the duty cycle greater than 33% of the time during sleep stage(s) corresponding to slow brain waves.
 19. The method of claim 15, wherein the current generation device is adapted to turn off the duty cycle corresponding to a detected sleep stage corresponding to fast or rapid brain waves.
 20. The system of claim 15, wherein the system is adapted to check impedance of the at least two electrodes when the duty-cycle is off. 